ABSTRACT
Chapter 1 is the introduction to the study on high-performance tensegrity-based metamaterials and structures. It introduces several concepts which are essential for this book, such as: tensegrity systems, mechanical metamaterials, and extremal materials. Tensegrities are pin-jointed structural systems consisting of cables (elements in tension) and struts (elements in compression), with infinitesimal mechanisms balanced with self-stress states. They have numerous advantages, which make them perfect for applications in smart systems and systems with extremal mechanical behaviour. Extremal materials were introduced in 1995 by Graeme Milton and Andrej Cherkaev, and they should be understood as systems with extremely large stiffness in some modes of deformation and extremely compliant behaviour in others. In this book, the concept of extremal materials is applied to tensegrity metamaterials as well as bigger structural systems, such as cellular lattices, whose inner architecture resembles that of cellular metamaterials, but which are aimed at civil engineering applications in a non-material scale. They can be designed in such a way that they exhibit a variety of unusual properties, e.g.: a negative Poisson's ratio, a vanishing shear modulus, negative compressibility or negative stiffness, as well as extremal mechanical properties.
